Conventionally, when detecting an extremely small amount of substance, a variety of sample detection devices capable of detecting such a substance by application of a physical phenomenon of the substance have been used.
One example of such sample detection devices is a surface plasmon resonance device (hereinafter, referred to as “SPR device”) which is made to detect, for example, an extremely small amount of analyte in a living body, by applying a phenomenon in which resonance between electrons and light in a minute region of a nanometer level or the like yields a high optical output (surface plasmon resonance (SPR) phenomenon).
Another example of the sample detection devices is a surface plasmon-field enhanced fluorescence spectroscopic measurement device (hereinafter, also referred to as “SPFS device”) which is capable of detecting an analyte with higher accuracy than an SPR device based on the principle of surface plasmon-field enhanced fluorescence spectroscopy (SPFS) where surface plasmon resonance (SPR) phenomenon is applied.
In this surface plasmon-field enhanced fluorescence spectroscopy (SPFS), in a condition where attenuated total reflection (ATR) of an excitation light such as a laser light irradiated from a light source occurs at the surface of a metal thin film, a surface plasmon light (compressional wave) is generated from the surface of the metal thin film, thereby the amount of photons included in the excitation light irradiated from the light source is increased by several ten times to several hundred times so as to obtain an electric field-enhancing effect of the surface plasmon light.
In cases where such an SPR device or SPFS device is used to detect an extremely small amount of substance, it is required that a reaction section in which a ligand is immobilized on a metal thin film to be irradiated with an excitation light be washed or replaced for each sample to be detected.
Therefore, as disclosed in Patent Documents 1 to 3, by using a sensor chip having a constitution that comprises: a substrate (transparent support); a metal thin film formed on the substrate; and a reaction section in which a ligand is immobilized on the metal thin film, a sample can be easily inspected.